CREATE TABLE IF NOT EXISTS refresh_tokens (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  token_hash TEXT NOT NULL UNIQUE,
  expires_at TIMESTAMPTZ NOT NULL,
  revoked_at TIMESTAMPTZ,
  created_at TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX IF NOT EXISTS idx_refresh_tokens_user_id ON refresh_tokens (user_id);
CREATE INDEX IF NOT EXISTS idx_refresh_tokens_token_hash ON refresh_tokens (token_hash);